BRUES: PARASITIC HYMENOPTERA. 105 



the armature of the third abdominal segment is not hke that of the 

 type-species. It will easily run down to the genus in Ashmead's 

 Genera of Ichneumon flies ^ and his emendation of the same ^ given 

 in connection with the description of the genus. In habitus the 

 species is very much like a Chelonus, but is structurally very different. 



ACANTHORMIUS DUBITATUS, Sp. nOV. 



Type. — M. C. Z. 9,055. Solomons: Three Sisters, Malapaina. 

 W. M. Mann. 



9 . Length 2.3 mm. Uniformly ferruginous, the legs and three 

 basal joints of antennae pale yellow. Face evenly convex, smooth 

 and shining; malar space one third as long as the eye; clypeal emargi- 

 nation deep, leaving a large semicircular opening above the mandibles. 

 Front and posterior part of head polished, the latter very strongly 

 margined. Antennae 21-jointed; scape short, oval; pedicel more 

 than half as large as the scape; flagellar joints long, gradually decreas- 

 ing in length toward apex, basal ones cylindrical, apical ones becoming 

 more or less lanceolate. Mesonotum highly polished with deep 

 crenulate parapsidal furrows that converge and meet before the scutel- 

 lum; also with a median furrow impressed only behind; scutellum 

 with two large, quadrate, nearly confluent foveae at the base. Pro- 

 podeum areolated, the superomedian area an equilateral triangle 

 connected with the anterior margin by a median carina, petiolar area 

 pentangular, long, narrowed below. Abdomen consisting of three 

 segments, the second longest, about as wide as long; third a little 

 shorter; first one third shorter; upper surface coarsely longitudinallj^ 

 striated or wrinkled; third segment deeply emarginate at apex and 

 also at the middle of each side, with a small tooth just preceding the 

 lateral emargination ; venter pale; ovipositor shorter than the first 

 segment. Propleura with several coarse striae below, mesopleura 

 convex, polished, with a few coarse striae converging from the upper 

 anterior margin toward the centre of the disc; below with a deep 

 elongate impression and just inside the posterior edge with a crenate 

 line; metapleura coarsely rugose. Wings nearly hyaline, with pale 

 brown veins ; submedian cell slightly longer than the median ; stigma 

 elongate; second section of the radius one third longer than the first; 



1 Proc. U. S. N. M., 1000, 23, p. 148. 



2 Ibid., 1906, 30, p. 200. 



